Tilly And The Wall, Luminaire, London <!-- none onestar twostar fourstar fivestar -->

They don't know what they're doing. Tilly and the Wall's two female singers, and the tap-dancer they use in place of a drummer, can hardly hear themselves on stage, as faulty mics and monitors reduce the close harmonies and tap-beats to a semi-audible shambles. It says something for the indomitable, adolescent spirit of play that is the heart of their appeal that the crowd stick around for the ride, and are rewarded with a memorably shaky show.

Tilly and the Wall are the latest beneficiaries of the Omaha affect. The weird gravitational pull that Conor Oberst, the singer-songwriter also known as Bright Eyes, has exerted over his hometown in Nebraska in the last few years has seen uniformly excellent bands drawn to the label he's on, Saddle Creek, and his own label, Team Action. The latter is the US home to Willy Mason, Rilo Kiley and Tilly and the Wall, an Americana line-up defined by fragile but defiant individualism. Tilly's own attributes are suggested by their debut's title, Wild Like Children. They shun the compromises of maturity and professionalism in favour of youthful freedom. As to that tap-dancer, Jamie Williams, she is the can-do spirit of Judy Garland improbably transplanted to the indie nation.

This is just what's required as the sound collapses around them tonight. Williams is a vision of breathless enthusiasm, even when you can't hear the beats she's tapping. Guitarist Derek Pressnall compensates for the stuttering mics of Kianna Alarid and Neely Jenkins, who contribute shambling harmonies behind him. Stray lyrics float out of the mix, suggesting a mystical attitude to urban adventures and romance. "The city looked wonderful," Pressnall muses on "Fell Down the Stairs", before adding, "I know in my heart I would never let you tumble to the ground"; the sort of burning devotion which will always be in fashion.

Only when the sound finally kicks in near the end do we get a glimpse of Tilly And the Wall's potential. Alarid and Jenkins seem jolted with energy, and start to sing with harmonious power. By the encore, Williams' feet are back on the beat, just in time for their manifesto, "Nights of the Living Dead". A somehow still-innocent account of a night of unchecked hedonism, they drag some of the crowd onto their tiny stage as they sing, again and again: "I wanna fuck it up, and I feel so alive."

In the face of such pure feelings, the earlier trials don't matter so much.

www.tillyandthewall.com